Oxygen vacancies in amorphous silica: structure and distribution of properties
نویسندگان
چکیده
منابع مشابه
Structure, properties, and dynamics of oxygen vacancies in amorphous SiO2.
Oxygen vacancies in SiO2 have long been regarded as bistable, forming a Si-Si dimer when neutral and a puckered configuration when positively charged. We report first-principles calculations of O vacancies in amorphous SiO2 supercells that unveil significantly more complex behavior. We find that the vast majority of O vacancies do not pucker after capture of a hole, but are shallow traps. The r...
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Using density functional theory (DFT) calculations, we investigated oxygen vacancy diffusion and aggregation in relation to dielectric breakdown in amorphous silicon dioxide (a-SiO2). Our calculations indicate the existence of favourable sites for the formation of vacancy dimers and trimers in the amorphous network with maximum binding energies of approximately 0.13 eV and 0.18 eV, respectively...
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We modeled all stable positive and negative charge states of oxygen vacancies originating from the neutral O3 Si=Si O3 defect in amorphous SiO2 (a-SiO2) using an embedded cluster method on a distribution of structural sites. For the first time, we predict the geometry, electronic structure and spectroscopic properties of doubly ionized and negatively charged oxygen vacancies in a-SiO2 and demon...
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We use molecular dynamics computer simulations to study the equilibrium properties of the surface of amorphous silica. Two types of geometries are investigated: i) clusters with different diameters (13.5Å, 19Å, and 26.5Å) and ii) a thin film with thickness 29Å. We find that the shape of the clusters is independent of temperature and that it becomes more spherical with increasing size. The surfa...
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Based on first-principles density-functional calculations, we present the structure and diffusion of boron in amorphous silica, as well as in crystalline silica for comparison purpose. We find that incorporation of a boron atom into the amorphous silica matrix results in various minimum-energy configurations with and without oxygen deficient centers, and also the B-related defects can undergo i...
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ژورنال
عنوان ژورنال: Microelectronic Engineering
سال: 2005
ISSN: 0167-9317
DOI: 10.1016/j.mee.2005.04.083